Palsies of the Conjugate Ocular Movements

IN attempting to determine the site and cause of a lesion which affects a conjugate movement of the eyeballs in any direction, we must keep before us the complex physiological apparatus which regulates the normal movements of the eyes. For these occur not only in response to voluntary impulses, but also as reflex move- ments excited by peripheral stimuli arising in the retinae, in the ocular muscles themselves, in the labyrinths, in the cervical muscles, and even in response to auditory and cutaneous stimuli. Further, while some of these reflex movements, such as the adjustments of our eyes to changes in the position of our heads and bodies, depend on the activity of sub-cortical centres only, others require the intervention of the forebrain cortex.